化学实验操作技能遗忘进程的实验研究

以大学化学系新生为实验对象,以分析天平为实验材料,对化学实验操作技能的遗忘进程进行了实验研究,讨论了化学实验操作技能遗忘曲线理论,对实验结果进行了探讨,提出了改进化学实验教学,提高学习质量的看法和建议,从而补充了动作操作遗忘进程在化学实验操作技能中的遗忘规律。     

化学实验操作考查能否得到可信的评价结果——以初三物质鉴别实验为例

以内地新疆高中班预科学生完成初三化学课程中3种固体粉末的鉴别实验为例,了解实验操作考查的评分者间信度的具体情况和影响因素。在本研究中,2位评分者的评分有较大的差异和较低的一致性,评分者间信度较低。试题的复杂性、监考学生的人数、评分标准的设计、评分者对评分标准的理解这4方面影响着评分者间信度。建议实验操作考查组织者控制监考学生的人数,加强评分者的培训工作,真正发挥实验操作考查的评价功能。     

固体氧化物燃料电池综合实验的设计

设计了一个综合性实验——固体氧化物燃料电池制备及性能测试。实验内容包括电解质和电极粉体的制备、电池片压制、对称电极制备,以及采用X射线衍射对粉体结构进行表征,采用电化学工作站对电池化学性能进行测试分析。本实验不仅可以锻炼学生的基本实验操作技能,还可以提高学生的学习兴趣和动手能力,培养学生的创新意识和团队协作精神。     

苯胺四聚体合成及电致变色器件制备——一个大学化学综合性实验

介绍一个研究探索型大学化学综合性实验——苯胺四聚体合成及其电致变色器件制备。内容包括苯胺四聚体的合成及简单的电致变色器件的制备和相关性能的测试。通过本实验的实践,可以让学生拓宽相关化学专业知识,提高学生综合实验操作技能和专业素质,让学生接触所学领域的前沿技术,激发学生对科学研究的兴趣,培养科研探究能力。     

理论指导实践化学实验教学模式的建构及实践

教材中演示实验或探究实验是针对某一个实验原理引导学生学习化学知识与实验操作技能、验证化学原理、训练科学思维.理论指导实践的化学实验教学模式旨在引导学生用学习过的化学知识和化学实验技能对未知领域进行综合性探索,学习新知,培养创新能力.     

人教版初、高中化学教材实验技能训练的要求及衔接性分析

根据化学实验操作技能形成的4个阶段——操作定向、操作模仿、操作整合、操作熟练,探讨了人教版初、高中化学教材实验操作技能训练过程的衔接性问题,指出实验操作技能训练的层次性、渐进性和有效迁移性都体现了实验操作技能训练的衔接性.同时分析了人教版初、高中化学实验操作技能训练内容的衔接点,为一线教师更科学地运用教材提供参考.     

“基础化学”模块化、超市化递进式实验教学探索

针对目前"基础化学"理论和实验教学的现状,实行模块化、超市化实验项目建设,进行分层式、递进式开放实验教学探索。调查研究表明新的实验教学模式有利于弥补学生化学基础的不足,增强化学实验基本操作技能的训练,保障学生面向药学类各职业岗位所必须具备的操作技能,提高"基础化学"的教学效果,真正发挥"基础化学"对后续课程的支撑作用。     

席夫碱型有机小分子荧光探针的制备与表征——推荐一个综合化学实验

介绍一个综合型创新实验——有机小分子荧光探针的制备与表征。内容包括有机配体的合成及表征、荧光光谱的测试、金属离子的检测等。通过本实验的实践,既可以让学生更好地掌握无机、有机和分析化学相关专业知识,提升实验操作技能,又能让学生了解有机小分子荧光探针这一科研前沿领域,激发学生对科学研究的兴趣,培养科研能力。建议将本实验纳入本科高年级综合化学实验课。     

品味过程 反思不足 促进提高——农村化学教师实验技能的调查报告

介绍了2010年江苏省农村初中化学实验操作技能大赛的内容以及笔者参加比赛的感受和体会。针对比赛中出现的问题,提出了提高农村化学教师实验操作技能的一些建议。     

论化学实验操作技能考查成绩的评定

一、问题的提出1995年度,我校担任的省级课题《高中理科实验技能综合评价》的研究中,通过对本校高二年级240位同学的测试,题组成员发现,化学实验操作的准确程度,不是评价学生实验操作技能水平的唯一指标。其中操作速度是不容忽视的重要指标之一。我们在对15个化学实验操作点的考查中,240位参试学生速度最快的只用了15分钟,最慢的要32分钟完成为此,我们从全部8位教师监试的40组240名学生中,随机抽取3位教帅监试的匕纷共90名学生（每人监试5组,每组考生均为6入）作为样本,并以学生实验技能考查前的地学成绩为基准．讲行对比研究‘…     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.